feat(frontend): support create vector index on function expression

[wenym1]

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What's changed and what's your intention?

Support create vector index on functional expression

create index i on items using flat (get_embedding(text)) include(text) with (distance_type = 'l2');

Checklist

• I have written necessary rustdoc comments.
• I have added necessary unit tests and integration tests.
• I have added test labels as necessary.
• I have added fuzzing tests or opened an issue to track them.
• My PR contains breaking changes.
• My PR changes performance-critical code, so I will run (micro) benchmarks and present the results.
• I have checked the Release Timeline and Currently Supported Versions to determine which release branches I need to cherry-pick this PR into.

Documentation

• My PR needs documentation updates.

Release note

[wenym1]

• feat(frontend): support create vector index on function expression #22808 👈 (View in Graphite)
• feat(frontend): support vector search lookup join on non-covered columns #22773
• feat(frontend): convert to read vector index on covering vector index #22545
• feat(frontend): optimizer rule to convert vector top n to vector index read #22467
• feat(batch): support vector index nearest batch executor #22348
• feat(frontend): support create vector index on frontend #22432
• feat(streaming): implement vector index write executor #22241
• main

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[chenzl25]

LGTM